12.5" wide tire on stock 7.5" wheels?

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Howsitgoineh

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Hey all, I'm currently running 275/70r18 on my stock ram wheels. Have a 3.5" lift installed.
I'd really like to get some 35x12.5 18s put on it.

My question is, will the 12.5" wide tire fit on my stock wheels? I believe they are 7.5" wide.

I really like the stock wheels and would like to keep them. Might spacers be necessary to get the clearance for full lock?
 
Yep..they will fit fine on the wheel but they will wear a bit odd. Some brands If you run the recommend air pressure the tire gets a bit of a crown and prematurely wears the center, the more aggressive the tire the more pronounced the problem. I’ve ran 36x12.5x16 on stock steel 7.5” Superduty wheels with no problems, just ran the PSI as low as I could without the TPMS light coming on.

I hate spacers , if the tires are gonna hit I ether add a little more lift or do some trimming.
 
Back in the day it was pretty common to run a 15x8 with a 31/33/35x12.5 wide tire. Not so much anymore. The current trend before I sold my 15 F250 6.7 was to run 22x12 rims with 12.5 wide tires. That was horrible and it got worse from there with people running 14 wide wheels with stretched 12.50 tires. 12.50s on 7.5 wide wheels won’t look great imo, ballooned out. You’ll have to play with the tire pressure to get them to wear right.
 
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3.5” of lift sounds like a leveling puck spacer kit. Are you running a real lift?
 
the only thing i'd be woried about is rubbing on the frame and suspension when at full turn lock. you might want to look into either a small spacer or some different offset wheels if you get some rubbing
 
View attachment 11639333.5” of lift sounds like a leveling puck spacer kit. Are you running a real lift?
Running bilstein lift struts up front, and spacers in the back to level. The lift struts make for a real nice smooth ride. I hear the puck spacers make the ride stuff and rough due to spring compression

Side note, I love that tire size calculator. Awesome reference
 
Back in the day it was pretty common to run a 15x8 with a 31/33/35x12.5 wide tire. Not so much anymore. The current trend before I sold my 15 F250 6.7 was to run 22x12 rims with 12.5 wide tires. That was horrible and it got worse from there with people running 14 wide wheels with stretched 12.50 tires. 12.50s on 7.5 wide wheels won’t look great imo, ballooned out. You’ll have to play with the tire pressure to get them to wear right.
Thanks for the reply. I have heard they "balloon" out a little bit. For some, this looks really cool, and others not so much.

Just don't wanna mount these tires and go "ahhh well that looks like crap" and have to swap. I am ok to get new wheels, I just really like the stock ones.
Appreciate the tip on tire pressure, I saw that mentioned above. I do wanna get the full tread life out of these tires for sure.

If I get new wheels, what width would you recommend for a 12.5 tire?
 
Yep..they will fit fine on the wheel but they will wear a bit odd. Some brands If you run the recommend air pressure the tire gets a bit of a crown and prematurely wears the center, the more aggressive the tire the more pronounced the problem. I’ve ran 36x12.5x16 on stock steel 7.5” Superduty wheels with no problems, just ran the PSI as low as I could without the TPMS light coming on.

I hate spacers , if the tires are gonna hit I ether add a little more lift or do some trimming.
Thanks for your input, it really helps.

Just out of curiosity, why is it you're not a fan of spacers?
I don't necessarily want or need them on my rig, just like to get all the info I can before I make my final decision
 
My question is, will the 12.5" wide tire fit on my stock wheels? I believe they are 7.5" wide.
What year and model?

35x12.50R18 tires are approved for 8.5-11" wide wheels. Lots of them running on 8" wheels, but 7.5" is a little narrow for me personally. (Actually 12.50 is wide for me... i like a tall skinny tire, like a 305/85R16) The good news is I think you probably have an 8" wheel stock. Beware that some stores won't even install them on wheels that aren't within spec for the tire.

A narrow wheel and tire generally works better on a Ram. Might have to check the rear of the front wheel opening for most likely contact on turning.
 
What year and model?

35x12.50R18 tires are approved for 8.5-11" wide wheels. Lots of them running on 8" wheels, but 7.5" is a little narrow for me personally. (Actually 12.50 is wide for me... i like a tall skinny tire, like a 305/85R16) The good news is I think you probably have an 8" wheel stock. Beware that some stores won't even install them on wheels that aren't within spec for the tire.

A narrow wheel and tire generally works better on a Ram. Might have to check the rear of the front wheel opening for most likely contact on turning.
I'm playing around a bit with tire sizing, if I can go a bit more narrow I just might so I can keep the stock wheels on her. It's a 2020 ram 1500 tradesman, quad cab w/ 5.7l Hemi
 
So you’re planning to run Billy 5100s up front? No lift spring and preload the suspension moving up with the clips to achieve the lift? 12.5 tires need 10” wide wheels to look right imo.
I had them installed a couple years ago. Just the 5100s on the front, and I then went up to the 33s. They are bald and I wanna run 35s

Again I appreciate the input, I'll see what is available. Though I may go with a slightly more narrow tire to suit the stock wheel
 
I'm playing around a bit with tire sizing, if I can go a bit more narrow I just might so I can keep the stock wheels on her. It's a 2020 ram 1500 tradesman, quad cab w/ 5.7l Hemi
Yeah, that should be an 18x8" wheel. Can check the cast marking on the back side to confirm.

If you haven't found it yet, the tiresize.com website mentioned earlier has listings by diameter. Great resource I use often. Below is what is shown for 34" diameter for example. These are nominal sizes that vary by manufacturer of course, so best to refer to specs or real life measurements.

18" Wheel Size​

285/75R18 = 34.8x11.2R18
295/70R18 = 34.3X11.6R18
305/70R18 = 34.8x12R18
325/65R18 = 34.6x12.8R18
34X12.5R18
 
Side note, I thought we were talked about a 3/4 ton truck, Most of what you’re going to find in that size range is E rated load. Do you currently have E rated tires? If not you understand they’re going to be much heavier and stiff right? I put E rated tires on my T4R for the added sidewall ply for puncture resistance off-road but it definitely made the on road ride worse.
 
Side note, I thought we were talked about a 3/4 ton truck, Most of what you’re going to find in that size range is E rated load. Do you currently have E rated tires? If not you understand they’re going to be much heavier and stiff right? I put E rated tires on my T4R for the added sidewall ply for puncture resistance off-road but it definitely made the on road ride worse.
Yep, I have noticed most of these tires are 10 or even 12 ply E rated. I am running Hercules T/X currently. Put them on after I got several punctures in the stock Goodyears over time.
They are noticeably heavier and louder when on the pavement, but they ride exceptionally well.

Forgot to mention the truck also has the off-road package from factory, so the gear ratio is suitable for larger tires and I am ok with taking a loss on mpg
 
Thanks for the reply. I have heard they "balloon" out a little bit. For some, this looks really cool, and others not so much.

Just don't wanna mount these tires and go "ahhh well that looks like crap" and have to swap. I am ok to get new wheels, I just really like the stock ones.
Appreciate the tip on tire pressure, I saw that mentioned above. I do wanna get the full tread life out of these tires for sure.

If I get new wheels, what width would you recommend for a 12.5 tire?
I ran a 8" wheel with 12.50 35's
BFG's for over 20 years. Just adjust the air pressure a little. It doesn't take much psi to get a good wear patch.
This was back in the 16" & 16.5" days. 😆
I still don't understand the foolish 20"+ low profile and super wide with spacers on a 3/4 or one ton 4wd pickups.
 
I ran a 8" wheel with 12.50 35's
BFG's for over 20 years. Just adjust the air pressure a little. It doesn't take much psi to get a good wear patch.
This was back in the 16" & 16.5" days. 😆
I still don't understand the foolish 20"+ low profile and super wide with spacers on a 3/4 or one ton 4wd pickups.
My first truck was a Chevy S-10
The previous owner had slammed it. I brought it back to stock height and put the original tire size back on it, 16" wheels

A lot of people think it looked cool with the suspension drop, but it couldn't haul anything and had no ground clearance. Bumped on every curb, and was useless in the snow. Essentially, as a truck it just wouldn't work as it is intended to.

I have seen on a few truck forums and keep forums 35 12.5 r18s on 8" wheels with no issues
Appreciate the info buddy, thanks. I'm gonna slap the 35s on my stock wheels and see how it goes!
 
I have seen on a few truck forums and keep forums 35 12.5 r18s on 8" wheels with no issues
Appreciate the info buddy, thanks. I'm gonna slap the 35s on my stock wheels and see how it goes!
Yeah, this was back when you could buy decent American Racing aluminum wheels for $100! Dam that makes me feel old.🤨
 
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